Butt Craig M, Hoffman Kate, Chen Albert, Lorenzo Amelia, Congleton Johanna, Stapleton Heather M
Nicholas School of the Environment, Duke University, Durham, NC 27708, United States.
Environmental Working Group, Washington DC 20009, United States.
Environ Int. 2016 Sep;94:627-634. doi: 10.1016/j.envint.2016.06.029. Epub 2016 Jul 7.
The use of alternative chemical flame retardants in consumer products is increasing as the result of the phase-out of polybrominated diphenyl ethers. Today, the most commonly detected alternatives in residential furniture include the organophosphate flame retardants (PFRs) and the Firemaster (R) 550 mixture (FM550). Urinary levels of dialkyl and diaryl phosphate esters, and 2-ethylhexyl tetrabromobenzoate (EH-TBB) have been used as biomarkers of human exposure to PFRs and FM550, respectively. In a previous study, we demonstrated that toddlers had significantly higher levels of PFRs relative to their mothers in a cohort from New Jersey; however, it is unclear if there are regional differences in exposure. It is possible that exposure to PFRs may be higher in California relative to other US States due to the California flammability standard, as was seen previously observed for PBDEs. In the current study, we examined urinary levels of PFR metabolites and TBBA in 28 mother-child pairs from California, USA, collected in 2015, and compared them with levels measured in our previous study from New Jersey. Urine samples were extracted using solid-phase extraction and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Diphenyl phosphate (DPHP), isopropyl-phenyl phenyl phosphate (ip-PPP), bis(1,3-dichloro-2propyl) phosphate (BDCIPP) and BCIPHIPP conjugates were detected in 100% of mother and child urine samples, while bis(1-chloro-2-propyl) phosphate (BCIPP), tert-butyl-phenyl phenyl phosphate (tb-PPP) and TBBA were detected in < 50% of samples. Interestingly, BCIPHIPP conjugates were detected in 100% of the urine samples, suggesting ubiquitous exposure to the parent compound, tris(1-chloro-2-propyl) phosphate (TCIPP). The current study found significantly higher BDCIPP levels in California toddlers and higher and ip-PPP levels in mothers as compared to the New Jersey cohort, which may be reflective of California's furniture flammability standard. For example, BDCIPP levels in California children were 2.4 times higher than those in New Jersey children. Consistent with our previous work, the current study showed higher PFR and EH-TBB exposure in children, likely due to increased hand-mouth behavior. Children's DPHP and BDCIPP levels, on average, were 5.9 times and 15 times those of their mothers. Positive correlations between paired mothers and their children were shown for DPHP and BCIPHIPP conjugates but not BDCIPP or ip-PPP. In the children, several predictors of hand-mouth behavior were associated with BDCIPP, DPHP and ip-PPP urine levels, but no associations were observed with BCIPHIPP conjugates.
由于多溴二苯醚的逐步淘汰，消费品中替代化学阻燃剂的使用正在增加。如今，在住宅家具中最常检测到的替代品包括有机磷酸酯阻燃剂（PFRs）和Firemaster（R）550混合物（FM550）。二烷基和二芳基磷酸酯以及2-乙基己基四溴苯甲酸酯（EH-TBB）的尿样水平已分别用作人体接触PFRs和FM550的生物标志物。在先前的一项研究中，我们证明，在新泽西州的一个队列中，幼儿体内的PFRs水平相对于其母亲显著更高；然而，尚不清楚暴露情况是否存在地区差异。由于加利福尼亚州的易燃性标准，相对于美国其他州，加利福尼亚州的PFRs暴露水平可能更高，就像之前观察到的多溴二苯醚的情况一样。在本研究中，我们检测了2015年从美国加利福尼亚州采集的28对母婴的尿样中PFR代谢物和TBBA的水平，并将其与我们之前在新泽西州的研究中测得的水平进行比较。尿样采用固相萃取法提取，并通过液相色谱串联质谱法（LC-MS/MS）进行分析。在100%的母婴尿样中检测到了磷酸二苯酯（DPHP）、异丙基苯基苯基磷酸酯（ip-PPP）、双（1,3-二氯-2-丙基）磷酸酯（BDCIPP）和BCIPHIPP缀合物，而在不到50%的样本中检测到了双（1-氯-2-丙基）磷酸酯（BCIPP）、叔丁基苯基苯基磷酸酯（tb-PPP）和TBBA。有趣的是，在100%的尿样中检测到了BCIPHIPP缀合物，这表明母体化合物三（1-氯-2-丙基）磷酸酯（TCIPP）普遍存在暴露情况。本研究发现，与新泽西州队列相比，加利福尼亚州幼儿体内的BDCIPP水平显著更高，母亲体内的ip-PPP水平更高，这可能反映了加利福尼亚州的家具易燃性标准。例如，加利福尼亚州儿童体内的BDCIPP水平是新泽西州儿童的2.4倍。与我们之前的研究一致，本研究表明儿童体内的PFR和EH-TBB暴露水平更高，这可能是由于手口行为增加所致。儿童的DPHP和BDCIPP水平平均分别是其母亲的5.9倍和15倍。配对的母亲和孩子之间，DPHP和BCIPHIPP缀合物呈正相关，但BDCIPP或ip-PPP则不然。在儿童中，手口行为的几个预测因素与BDCIPP、DPHP和ip-PPP的尿样水平相关，但未观察到与BCIPHIPP缀合物有关联。
